It's not easy finding another anime like Assassination Classroom. After all, how many shows out there star a giant squid creature teaching his class of assassins to kill him, or else he'll blow up the Earth? With that said, there are actually a lot of anime that embody the same wacky and psychotic spirit of Assassination Classroom. Some take the high school anime genre to new heights; others share the same bloodlust for action. If you want another anime like Assassination Classroom, then this is the list for you.
Check out the list of similar series below and vote up the ones you think are best.
If you want a more optimistic approach to Assassination Classroom, then My Hero Academia is the anime for you. Instead of students learning to master the art of assassination to kill their teacher and save the world, My Hero Academia is about a class of young superheroes learning how to protect the world from comic book style evildoers. The teacher/apprentice relationship between Izuku "Deku" Midoriya and his idol superhero, All Might, is nothing short of charming.
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Danganronpa The Animation comes the closest to matching the style of Assassination Classroom, as both shows place their young characters in a "kill or be killed" situation. In the case of Danganronpa The Animation, the students of Hope's Peak Academy must eliminate each other if they ever want to get out alive. Cheering them on is a creepy teddy bear instructor named Monokuma, who serves as the Koro-sensei of the series.
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Angel Beats! adds a spiritual twist to the everyday high school setting by depicting it as a limbo for teenagers not ready to pass on. Yuzuru Otonashi is the latest student enrolled in the high school afterlife, however, he finds himself caught in a war between the students and the angelic student council president Kanade Tachibana. Fans of Assassination Classroom will appreciate the clever take on high school life. Both shows also share the same anime director, Seiji Kishi, so, the same comedic style you loved in Assassination Classroom is also here in Angel Beats!
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Baka and Test: Summon the Beasts
For another anime with an interesting high school premise, check out Baka and Test: Summon the Beasts. Similar to Assassination Classroom, the students in Baka and Test are fighting amongst each other to raise their status quo. In this case, the lower-class students of Class F are fighting their betters by summoning beasts who are as strong as the student's past test score.